▪ Abstract Vitamin B12 is a complex organometallic cofactor associated with three
subfamilies of enzymes: the adenosylcobalamin-dependent isomerases, the …

The primarily function of cobalt in humans is based on its role in cobalamin (Cbl, vitamin B
12). Therefore, this chapter will focus on the physiological roles of Cbl and the importance of …

Many algae are auxotrophs for vitamin B12 (cobalamin), which they need as a cofactor for
B12‐dependent methionine synthase (METH). Because only prokaryotes can synthesize the …

The crystal structure of a 27-kilodalton methylcobalamin-containing fragment of methionine
synthase from Escherichia coli was determined at 3.0 Å resolution. This structure depicts …

Two X-ray structures of cobalamin (B12) bound to proteins have now been determined.
These structures reveal that the B12 cofactor undergoes a major conformational change on …

Cobalamin cofactors play critical roles in radical-catalyzed rearrangements and in methyl
transfers. This Account focuses on the role of methylcobalamin and its structural …

Porcine liver betaine-homocysteine methyltransferase (BHMT; EC) was purified to
homogeneity, and the Michaelis constants for betaine, dimethylacetothetin, and L …

The production of bulk chemicals mostly depends on exhausting petroleum sources and
leads to emission of greenhouse gases. Within the last decades the urgent need for …

Methionine synthase reductase (MSR) catalyzes the conversion of the inactive form of
human methionine synthase to the active state of the enzyme. This reaction is of paramount …

Vitamin B12 (cobalamin, Cbl) is an essential nutrient in human metabolism. Genetic
diseases of vitamin B12 utilisation constitute an important fraction of inherited newborn …